<?php

$thread_pool = array();
for ($i = 0; $i < 1200; $i++) {
    $handle = popen(sprintf('php ./http.php %d %d', $i*100, ($i+1)*100), 'r');

    $thread_pool[] = $handle;
}

while (TRUE) {
    foreach ($thread_pool as $handle) {
        echo fread($handle, 8192);
    }
}